Taxol synthesis: Synthesis of A-ring and a methodology for substituted cyclohexadienes
作者:J.S. Jadav、Dale Srinivas
DOI:10.1016/s0040-4039(97)10038-7
日期:1997.11
A fully functionalised synthesis of taxolA-ring, through Michael/Wittig reaction and regioselective opening epoxide as key steps and also a methodology for substituted cyclohexadienes through tandem Michael/Wittig reaction is described.
Ene-type reaction of “activated sulfoxide” with non-activated olefin. Counter-ion dependent (1,2)- . [3,2] shift dichotomy of ylides derived from allylsulfonium salts
作者:V.V. Veselovsky、V.A. Dragan、A.M. Moiseenkov
DOI:10.1016/s0040-4039(00)82417-x
日期:1988.1
Lithium perchlorate-accelerated ene-type reaction of an “activated sulfoxide” with non-activated trisubstituted olefin to give respective allylsulfonium salt and counter-ion dependent (1,2) - . [3,2] rearrangement of the ylide generated from this salt are discussed.
Ring-labeled retinoids and intermediates, and methods for their
申请人:Ligand Pharmaceuticals Incorporated
公开号:US05514821A1
公开(公告)日:1996-05-07
Methods for the synthesis of dideuterium and/or ditritium ring-labeled retinoids and intermediates, and their use in the discovery of Retinoid X Receptor ligands are provided. In addition, dideuterium and/or ditritium ring-labeled retinoids and novel intermediates, as well as methods for their use in ligand binding and mass spectral studies are also provided.
Syntheses of High Specific Activity 2,3- and 3,4-[3H]2-9-cis-Retinoic Acid
作者:Youssef L. Bennani、Marcus F. Boehm
DOI:10.1021/jo00110a023
日期:1995.3
B-cis-Retinoic acid (9-cis-RA) is an endogenous hormone which binds and activates the retinoic acid receptors (RARs) and the retinoic X receptors (RXRs). In order to investigate the function of 9-cis-RA in vitro and in vivo high specific activity labeled 9-cis-RA was prepared. Two tritium labels were efficiently introduced at the 2,3- or 3,4-positions, respectively, in the cyclohexene ring moiety resulting in labeled 9-cis-RA with specific activity of 58-60 Ci/mmol. The critical ring-labeling step relies on a highly regioselective tritiation of either a terminal or an isolated double bond in the presence of the conjugated retinoate side chain. Moreover, the labeling is performed at the penultimate synthetic step resulting in optimization of radiochemical yields and ease of synthesis. This is the first reported synthesis of ring-labeled [H-3](2)-9-cis-RA, and the methodology described herein is applicable to the synthesis of other retinoic acid isomers.
An ene-type reaction between an unactivated olefin and an ?activated? sulfoxide, and some properties of the resulting sulfonium salts
作者:A. M. Moiseenkov、V. A. Dragan、V. V. Veselovskii